Because of a number of factors, not the least important of which is the rising cost of gasoline, the development of fuel efficient automobiles has become an urgent project of the world's technological community. Nor is there any indication that fuel costs will decline in the foreseeable future so as to reduce the importance of the development of more fuel efficient cars.
A number of factors bear upon the efficiency of the typical internal combustion engine used in the majority of automobiles produced in the United States and other countries. One of these factors is the degree to which the air/gasoline mixture introduced into the cylinders of the engine is vaporized. Many carburetors, which effect this function, currently in use on automobiles today do not effectuate sufficient vaporization in order to maximize the engine efficiency.
Degree of vaporization is basically the function of two factors: (1) the amount of dispersal and atomization of fuel droplets at the time the fuel is combined with air; and (2) the temperature of the mixture as it is introduced into the cylinders of the engine for combustion. With respect to the first of these factors, the typical carburetor relies upon a reduced pressure created within an induction pipe by an increased velocity of air flow to atomize gasoline being sucked out of a choke tube. Frequently, this process is not adequate to accomplish a desired degree of atomization.
With respect to the second factor, heating of air introduced into the induction pipe prior to its entry therein is relied upon to raise the temperature of the air/fuel mixture to the necessary level. An inadequately heated mixture often results since the temperature of the gasoline is lower than that of the air as it enters the induction pipe. Consequently, a transfer of heat energy from the air to the gasoline occurs at time of mixing, and the heated air temperature becomes lowered. Additionally, heat is expended during the vaporization process. A final cause of heat loss is the transfer of thermal energy from the air between the time it absorbs heat from the engine exhaust until the time it enters the induction pipe.
Another factor which reduces the efficiency of the automobile engine while it is operating is the inability to selectively regulate the relative amounts of air and gasoline which make up the mixture going into the cylinders in response to the conditions under which the car is being operated. During acceleration periods, a greater percentage of gasoline with respect to the percentage of air in the mixture is necessary than at higher highway cruising speeds. At these higher speeds and under conditions in which there is not frequent acceleration and deceleration, however, the percentage of gasoline with respect to the percentage of air can be significantly reduced without any appreciable reduction in efficiency of the automobile engine. Typically, cars commercially available on the market do not include mechanisms for selectively varying the air/gasoline ratio of the mixture being introduced at the cylinders of the engine.
It is these problems extant in the art to which the invention of the present application is directed. It provides a structure which causes the air/gasoline mixture to be heated virtually up until the point at which the mixture enters the engine cylinders. Additionally, it effectuates more complete atomization of the gasoline prior to it being combined with air so that more complete vaporization will occur. It also provides means for selectively regulating the volumes of both air and gasoline which combine to form the mixture introduced into the cylinders.